Built to tackle the time‑consuming, manual work that gets in the way of real work, our tools automate everything from travel bookings to expenses, invoice processing, and more. By eliminating this shadow work that wastes hours, erodes morale, and saps innovation, we’re on a mission to power real work, with real impact. Founded in 2015, Perk has grown into a global company of more than 1,800 people across 12 offices globally, with headquarters in London and Boston. Are you a Software Engineer who thrives on real ownership? This means taking responsibility for the entire lifecycle of a feature, from being part in understanding what our customers' pains are with our product team, design documents, coding to deployment, and measuring impact. Engineering excellence here is measured by the reliability and simplicity of the systems you build to power a global platform. Join the Billing team Every day, tens of millions of dollars in bookings flow through systems the Billing team owns — and we're investing in the customer-facing side of that for the first time. We're building out the billing experience: the pages our customers use to directly interact with billing — invoices, payments, tax details, and more. Working closely with our product designer and PM, you'll own this frontend experience end-to-end, from design handoff through to shipped, polished product. As the team's first dedicated frontend hire, you'll have real influence over how this area is architected from the ground up, and space to establish frontend practices and standards as the team's frontend footprint grows. You'll be joining a team in the middle of significant technical change more broadly — re-platforming core billing flows to fault-tolerant, event-driven systems, scaling AI-driven invoice processing, and building out a tax engine used across trains, hotels, flights, and cars.



You won't own that backend work directly, but you'll be embedded in a team tackling problems at real scale, and there's plenty of room to get involved beyond the frontend if that interests you. You'll join a cross-functional squad where you have real ownership of a piece of Perk’s domains, a genuine say in what gets built, and the autonomy to make it happen. We care about impact, and we trust our people to deliver it. On the engineering side, it spans the whole workflow: our Notion, Jira, GitHub and Slack are AI-connected so you get up to speed fast, and day‑to‑day it helps with specifying features, writing and reviewing code, and automated AI PR review on every pull request. When something goes wrong in production, AI surfaces context across systems quickly. The bar is understanding your code and owning what you produce. Some examples of what it means to be a Senior at Perk At Perk, senior engineers are expected to go beyond the technical solution and focus on the problem itself. When a big change is needed in how our frontend platform works, you'll be the one writing the design documents that lay the foundation. You'll become a guardian of your team's technical quality; Your job is to make sure we're always investing our energy where it counts most. Whether it's coordinating a cross‑squad initiative, contributing to one of our engineering guilds (where engineers from different teams align on shared technical topics),



or pairing with architects on solution discovery, you'll operate comfortably beyond your immediate team. Senior engineers at Perk are mentors, coaches, and bar raisers. de-risks ambiguous projects through spikes and prototyping. Frontend Architecture: Architects scalable, evolvable React applications and component/data models that account for performance, state management, and long‑term maintenance. Ownership of Customer-Facing Experience: Comfortable taking a set of customer-facing pages from design handoff through to shipped, polished product — this role is the team's first dedicated frontend hire, so you'll help set the standard as the frontend footprint grows. Defines and upholds engineering excellence, including CI/CD optimizations, testing strategies (unit, integration, E2E/Cypress), and coding standards across the frontend stack. Frontend Strategy: Establishes frontend architecture patterns, including state management, performance budgets, accessibility, and comprehensive testing. Leads observability and frontend performance monitoring; Security & Risk: Oversees frontend security practices, including secrets hygiene, dependency risk management, and secure handling of sensitive billing/payment data in the UI. Levels up the engineering organization through active mentorship, leading design reviews, and influencing the product roadmap with technical data. At Perk, we take an IRL‑first approach to work, where our team works together in‑person 3 days a week. For certain roles, we can help with relocation from anywhere in the world, English is the official language at the office. Please submit your resume in English if you choose to apply. Perk is a integral company with a diverse customer base, and we want to make sure the people behind our product reflect that.

📌 Senior Frontend Engineer - Billing (Barcelona)
🏢 Perk
📍 Barcelona